Which sentence supports the conclusion that the Wright brothers refused to let setbacks stop them? "On August 9, when Wilbur tried to turn the glider, he crashed nose- first into the ground, banging his head against a wooden strut." "He'd thought there would be all the time in the world to plan his moves, to look around him, and to experience life from the air." "On the train home, Orville said what both of them were feeling: 'Not within a thousand years will man ever fly.' " "Instead they decided to go back to the beginning and think through everything they had done."